ויעלו את הצפרדעים, the ones produced by the sorcerers were unable to reproduce themselves, as were those that Aaron had produced. The sorcerers were never able to produce any creature that could move on its own. [It is important to realise that our author considers the צפרדע as a type of crocodile, the major danger to humans and fish inhabiting the Nile. Ed.]

'העתירו אל ה, he did pay attention to the aspect of getting rid of this plague, recognising that there was some use in calling on the G’d of the Israelites to remove the plague.

למתי אעתיר לך?. In order that you will recognise the difference between what your sorcerers are able to do and what G’d is capable of doing. When Moses offered two scenarios to Pharaoh, i.e. when the crocodiles would die, and henceforth restricting them to the river Nile, he also had in mind that whatever the sorcerers had done would be strictly limited in duration, and things would return to normal, whereas G’d could maintain the changes He had effected in nature indefinitely, totally or partially as He wished.

כדברך, in accordance with your wish. You had stipulated that the crocodiles should be removed from yourself, and from your people,” (verse 4) you did not ask for them to be eliminated from nature as a species.

למען תדע כי אין כה' אלוקנו, that there is no power in the universe other than the G’d of the Israelites who possesses the power to fundamentally effect changes in natural law. At that time, consigning crocodiles exclusively to the river Nile was a fundamental change in the habitat of this species. This species is different from all other known species in that instead of moving its lower jaw when eating, it moves its upper jaw. It also ingests food without excreting waste products. G’d will banish the species only from you and your houses, as this is all you asked for.

וסרו הצפרדעים, G’d will not only remove the ones which have already bothered you, but He will ensure that they will not again afflict you.

ממך ומבתיך, but not from the whole country; on the contrary, they will die in the land and cause a stench, but in the future they will not leave their habitat in or near the river.

ויצעק משה אל ה' על דבר הצפרדעים אשר שם לפרעה, Moses prayed that G’d remove only the crocodiles which had been sent against Pharaoh and his people, whereas any others should remain in the river. It required a special prayer, here described as an outcry, to ask G’d how to arrange the removal of this plague.

כי היתה הרוחה, even though the evil had not been removed totally, seeing that the stench of the dead beasts remained and putrefied the atmosphere, and these beasts remained in the river as a possible threat in the future.

והכבד את לבו, He reinforced his natural courage not to be frightened of a re-emergence of the crocodiles that had remained alive. He was also willing to put up with the stench of the decaying beasts. All of this rather than to admit his impotence vis-à-vis the G’d of the Israelites.

והך את עפר הארץ, they did not warn Pharaoh of the advent of this plague. Neither did they warn him before the onset of the שחין, the boils and blisters, nor before the darkness. The nine plagues, exclusive of the killing of the firstborn, were intended to serve as demonstrations of G’d’s power to change the laws of nature. Although the simultaneous dying of the firstborn was also a powerful such demonstration, it was intended as retribution for refusal to heed all the warnings G’d had extended to Pharaoh and his people. The first 3 plagues דצ'ך, demonstrated mastery of G’d over the two “heavy” components of the four basic elements the universe is made of, i.e. water and earth, The three plagues, abbreviated under the heading of עד'ש by Rabbi Yehudah Hanassi, demonstrates G’d’s control not only over inert parts of nature but also over living creatures. The third category בא'ח, demonstrated G’d complete control of the air, the atmosphere including the other two basic elements known as רוח and אש, air, wind, and fire. In each group the first two plagues were preceded by warnings, whereas the third was not. The matter has been alluded to in Job 33,29 הן כל אלה יפעל א-ל, פעמים שלוש עם גבר. “Truly, G’d does all these things, two or three times to a man.”

ולא יכולו. They were unable to produce anything which could truly move on its own.

וגם האדמה אשר הם עליה, a reference to the soil on which the houses stood which would become full of snakes and other creepers of the kind that inhabit the lower levels of the earth beneath its surface. The plague would result in the Egyptians feeling insecure in their homes even when they had shut every exit tightly.

ושמתי פדות בין עמי ובין עמך, so that even the few members of my people who might be in an area infested by the arov would not be molested by these beasts. The same beasts would harm your people on the same spot.

ויעתר, in order for G’d to remove the wild beasts at the time which Pharaoh had requested and in the manner he had asked for. We know that this time Pharaoh did not want to have to contend with the stench of the dead animals as he had had to when the crocodiles died on his territory, but that G’d made all these beasts retreat to where they had been before they had invaded the urban areas of Egypt. (compare verse 27)

גם בפעם הזאת, as he had done after the plague of the crocodiles had been removed. Seeing that the wild beasts had only retreated to their lairs and had not died, so that they still represented a potential threat, Pharaoh toughened his resolve and refused to send off the people.